The androgen-binding to rat prostate chromatin will be investigated by fractionation of chromatin protein fractions bound to radioactive androgen. Binding of androgens to chromatin will be carried out by incubation of minced prostate gland with 3H-dihydrotestosterone; or by translocation of cytosol-bound 3H-androgen to prostate nuclei, and subsequently isolating the chromatin. Two main androgen-binding chromatin fractions will be studied: the "acceptor" fraction obtained by extraction of chromatin with 0.35 M NaCl, and the residual fraction insoluble in 2 M NaCl which has also been found to actively bind androgens. The specificity of androgen-binding of these fractions and their effect and role in transcription will be determined. BIBLIOGRAPHIC REFERENCES: The role of the androgen-binding nonhistone proteins in the transcription of prostrate chromatin. L. M. Nyberg and T. Y. Wang. J. Steroid Biochem. 7, 267-273 (1976). Androgen-induced gene activation in the rat prostate. A-L. Hu, R.M. Loor and T. Y. Wang. Biochem. Biophys. Res. Commun. 73, 330-335 (1976).